Narcissism in social media reveals itself differently than in daily social interactions. Therefore, the present study aimed to develop a Scale of Narcissism in Social Media through the lens of the Narcissistic Admiration and Rivalry Model and to investigate its psychometric characteristics. The total sample of the study consisted of 740 participants between 18 and 65 years of age for exploratory and confirmatory factor analysis. The exploratory factor analysis resulted in a 16 item and two-factor structure. The structure of the scale was in accordance with the theoretical framework and therefore factors are named Narcissistic Admiration and Narcissistic Rivalry. The results of the confirmative analysis showed that the fit indices were acceptable. Correlations of the scale with other narcissism scales demonstrated concurrent validity and reliability analysis showed acceptable internal consistency. The results of the study show that the Scale of Narcissism in Social Media is a valid and reliable tool for measurement and data collection.